The Lancet Regional Health Western Pacific · Oct 24, 2026

Adult remaining life expectancy among Hong Kong-born and Mainland China/Macao/Taiwan-born residents in Hong Kong

By Chen X, Canudas-Romo V, Bishai DM

BACKGROUND: Hong Kong (HK) has among the world's highest life expectancy and a long history of immigration from Mainland China/Macao/Taiwan (MMT). Evidence remains limited on how differences between birthplace groups (HK-born vs. MMT-born) in longevity vary across ages and over time, how adult remaining life expectancy varies by length of stay (LOS) in Hong Kong within MMT-born residents, and which ages and causes of death account for observed gaps. METHODS: Using death registration and population denominators from the Hong Kong Census and Statistics Department (C&SD), we constructed sex- and birthplace-specific single-age-period life tables for 2006, 2011, 2016, and 2021, and estimated adult remaining life expectancy at age 15 (e₁₅). We used Arriaga decomposition to quantify age- and cause-specific contributions to birthplace group differences in e₁₅. Within MMT-born residents, we repeated the analysis by comparing LOS <10 years with LOS ≥10 years. FINDINGS: Across all study years and for both sexes, e₁₅ was higher among Hong Kong-born than MMT-born residents. Among females, the birthplace-group gap widened from 2.6 years in 2006 (72.2 years [95% CI 71.9-72.5] vs. 69.6 [95% CI 69.4-69.7]) to 3.3 years in 2011, before narrowing to 1.3 years in 2021 (72.8 [95% CI 72.6-73.0] vs. 71.5 [95% CI 71.3-71.7]). Among males, the gap widened from 3.4 years in 2006 (67.4 [95% CI 67.0-67.8] vs. 64.0 [95% CI 63.7-64.2]) to 4.8 years in 2016, before narrowing to 2.2 years in 2021 (68.7 [95% CI 68.5-68.8] vs. 66.5 [95% CI 66.3-66.7]). Among MMT-born females and males, shorter LOS was associated with higher e₁₅ than longer LOS in 2011 and 2016. In 2021, the female difference (shorter minus longer LOS) was 2.61 years (95% CI 0.88-4.53) with the 10-year cutoff, but -0.82 years (95% CI -2.27 to 1.07) with the 7-year cutoff. The corresponding male differences were -3.07 years (95% CI -4.27 to -1.57) and -7.04 years (95% CI -8.45 to -5.24), respectively. Age and cause decomposition showed that the birthplace gap was driven mainly by later-life mortality at ages 65-84 and 85+, and by pneumonia and cancers. INTERPRETATION: The observed adult survival advantage of Hong Kong-born over MMT-born residents persisted and was concentrated in later-life mortality, particularly from pneumonia and cancers. Although these descriptive differences should not be interpreted as causal effects of birthplace or LOS, the findings highlight potential priorities for migration-sensitive healthy ageing and mortality surveillance that accounts for place of birth, LOS, and cross-boundary mobility. FUNDING: Daniel and Mayce Yu Medical Development Fund (No. 200010837), and Australian Research Council (ARC DP210100401). The funders had no role in study design, data collection, data analysis, data interpretation, writing of the report, or the decision to submit the paper for publication.

doi.org/10.1016/j.lanwpc.2026.101998Open accessPubMed 42965056Populations